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Find your feet in the terminal

By the end: Find your current location, inspect a directory, and discover help without guessing.

The idea

A terminal is the interface; Bash is the shell interpreting your input. Commands usually follow command → options → arguments. A relative path starts at your current directory; an absolute path starts at /. Case matters: Notes and notes can be different files. The examples use Bash on GNU/Linux; optional programs may need your distribution's packages.

Your command toolkit

pwd

What it solves: Know which directory a command will affect.

bash
pwd

Prints your working directory. Check it before changing files; a relative filename is resolved here.

ls

What it solves: Inspect visible and hidden files.

bash
ls -lah

-l shows details, -a includes dotfiles, and -h makes sizes readable. A leading dot hides a name from the default listing, not from access.

cd

What it solves: Move between directories.

bash
cd /tmp
pwd
cd -

cd changes the current shell's directory. cd - returns to the previous directory; cd with no argument goes home.

dir

What it solves: Read another form of directory listing.

bash
dir .

GNU dir is similar to ls but normally formats entries in columns. Prefer ls in shared instructions because it is more familiar.

clear

What it solves: Make room for the next investigation.

bash
clear

Clears the display on supported terminals. It does not delete your command history or guarantee removal of terminal scrollback.

help

What it solves: Understand a Bash builtin.

bash
help cd

Builtins execute inside the shell. Bash help documents them; it is different from an external program's --help option.

man

What it solves: Read the installed program's manual.

bash
man ls

Press / to search, n for the next match, and q to leave the pager. Manual sections distinguish commands, files, and system calls.

whatis

What it solves: Get a one-line command description.

bash
whatis ls

Uses the local manual database. An empty result can mean missing manuals or an outdated index, not a missing executable.

apropos

What it solves: Find a command when you only know the job.

bash
apropos directory

Searches manual descriptions by keyword. Start with a broad word, then read the matching manual before trying options.

Before you move on

Try the guided lab below. Compare the result with the explanation, then record your reasoning in the workbook. A missing optional program or a restricted environment is something to explain, not a reason to change system settings blindly.

Practice with evidence

  1. Predict the result
  2. Run the guided lab
  3. Compare the output
  4. Explain your choice

A worked example

Guided lab

bash
pwd
ls -ld . /tmp
help pwd

What to expect: Two directory entries and help for pwd. Your current path will differ from another learner's.

Make it yours: Record your starting path, explain what . and .. mean, and name one option you discovered in help or a manual.

Read further

Apply what you learned

Your private practice

What does a relative path such as notes.txt depend on?

Answers are private. Completion requires the correct knowledge-check answer and a written response when an activity is included.

Restore a downloaded workbook

Choose a recovery file for this course and version. Review the recovered copy before saving it to your account.

Ask a question or report a problem

Describe what needs attention. Your private answer is shared only if you select the option below.

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